[PATCH bpf-next 1/2] bpf: xdp: allow offloads to store into rx_queue_index
From: Jakub Kicinski <hidden>
Date: 2018-05-09 02:37:24
Subsystem:
bpf [core], bpf [general] (safe dynamic programs and tools), bpf [networking] (tcx & tc bpf, sock_addr), networking [general], the rest · Maintainers:
Alexei Starovoitov, Daniel Borkmann, Andrii Nakryiko, Eduard Zingerman, Kumar Kartikeya Dwivedi, "David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Linus Torvalds
It's fairly easy for offloaded XDP programs to select the RX queue packets go to. We need a way of expressing this in the software. Allow write to the rx_queue_index field of struct xdp_md for device-bound programs. Skip convert_ctx_access callback entirely for offloads. Signed-off-by: Jakub Kicinski <redacted> Reviewed-by: Quentin Monnet <redacted> --- include/linux/bpf.h | 2 +- kernel/bpf/verifier.c | 2 +- net/core/filter.c | 9 ++++++++- 3 files changed, 10 insertions(+), 3 deletions(-)
diff --git a/include/linux/bpf.h b/include/linux/bpf.h
index 321969da67b7..a38e474bf7ee 100644
--- a/include/linux/bpf.h
+++ b/include/linux/bpf.h@@ -627,7 +627,7 @@ bool bpf_offload_dev_match(struct bpf_prog *prog, struct bpf_map *map); #if defined(CONFIG_NET) && defined(CONFIG_BPF_SYSCALL) int bpf_prog_offload_init(struct bpf_prog *prog, union bpf_attr *attr); -static inline bool bpf_prog_is_dev_bound(struct bpf_prog_aux *aux) +static inline bool bpf_prog_is_dev_bound(const struct bpf_prog_aux *aux) { return aux->offload_requested; }
diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c
index d5e1a6c4165d..d92d9c37affd 100644
--- a/kernel/bpf/verifier.c
+++ b/kernel/bpf/verifier.c@@ -5215,7 +5215,7 @@ static int convert_ctx_accesses(struct bpf_verifier_env *env) } } - if (!ops->convert_ctx_access) + if (!ops->convert_ctx_access || bpf_prog_is_dev_bound(env->prog->aux)) return 0; insn = env->prog->insnsi + delta;
diff --git a/net/core/filter.c b/net/core/filter.c
index cf0d27acf1d1..2336b90e8b26 100644
--- a/net/core/filter.c
+++ b/net/core/filter.c@@ -4911,8 +4911,15 @@ static bool xdp_is_valid_access(int off, int size, const struct bpf_prog *prog, struct bpf_insn_access_aux *info) { - if (type == BPF_WRITE) + if (type == BPF_WRITE) { + if (bpf_prog_is_dev_bound(prog->aux)) { + switch (off) { + case offsetof(struct xdp_md, rx_queue_index): + return __is_valid_xdp_access(off, size); + } + } return false; + } switch (off) { case offsetof(struct xdp_md, data):
--
2.17.0